A new study found that the novel coronavirus may enter the human brain through the nose. It said that the virus not only affects the respiratory tract, but also impacts the central nervous system (CNS), resulting in neurological symptoms such as loss of smell, taste, headache, fatigue and nausea.
The study, conducted by researchers from Charite-Universitatsmedizin Berlin, Germany, was published in the journal Nature Neuroscience. Although recent research has described the presence of viral RNA in the brain and cerebrospinal fluid, it remains unclear where the virus enters and how it is distributed within the brain, news agency Press Trust of India (PTI) reported. The researchers examined the nasopharnyx — the upper part of the throat that connects to the nasal cavity — a likely first site of viral infection and replication, and the brains of 33 patients — 22 males and 11 females — who died with the coronavirus infection. The median age at the time of death was 71.6 years, and the time from onset of COVID-19 symptoms to death was a median of 31 days, they said. The researchers said that they found the presence of SARS-CoV-2 RNA, the genetic material of the virus, and protein in the brain and nasopharynx, adding intact virus particles were also detected in the nasopharynx. The highest levels of viral RNA were found in the olfactory mucous membrane, they said.